of boston



J. KIEWICZ.

THREAD CONTROLLING DEVICE FOR SEWING MACHINES.

APPLICATION FILED MAYIS. I919.

1,326,669. I Patented Dec. 30,1919.

v lnven'ror. John Kiewicg byWMIM Afrys.v

Sometimes the buttonhole is cut immedi- UNITED STATES PATENT o FIo JOHN KIEWICZ, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE REEOE BUTTON HOLE MACHINE COMPANY, or BOSTON, massnorrusnrrs, A conronn'rron or MAINE.

TI-JIRIELAI)-CO1\TTROLLIN'G} DEVICE FOR SEWING-MACHINES.

Application filed May 15, 1919. ,Serial No. 297,366.

To all whom it may concern:

Be it known that I, JO N KIEwIoz, a citizen of the United States, residing at Boston, county of Suffolk, State of Massachusetts, have invented an Improvement in Thread-Controlling Devices for Sewing- Machines, of which the following description, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts. a

In some buttonhole sewing machines such, for instance, as illustrated in United States Patents No. 1,188,942, June 27, 1916, and No. 1,255,970, February 12, 1918, the under thread mechanism is carried by a rotary turret which is provided with a throat-plate through which the under thread is delivered, and means are also provided for delivering a stay-cord or filling thread to the buttonhole and laying it along the edge of the buttonhole as thestitching proceeds, so that the edge stitcheson the buttonhole will be formed over the stay-cord.

Buttonhole sewing machines of the abovementioned type are usually constructed'and, organized so that when the machine is started the first operationisto clamp the work, after which the parts are rnov ed to bring the work into-stitching position, and when the work is in stitching position, tthe stitch-forming mechanism is set in operation to form the edge stitches on the buttonhole.

ately after the work is clamped and'before the work is shifted into stitching pos tion, and sometimesthe buttonhole is out after a the stitching on the buttonhole has been completed. In either case the turret carrying the under thread mechanism is given a turning movement after one buttonhole has been completed and before the stitching on the next buttonhole begins, such turning movement operating to bring it into proper position for the beginning of the stitching on abuttonhole, and during this turning movement, the stay-cord or filling thread is some times subjected to a backward pull, tending vtoedraw it out offthe throat-plate.) 7

Some sewing machines of the above-mentioned type are provided with thread-cutting means which becomes operative after,

the completion ofa buttonhole to cut the stay-cord close to the work, in such a Specification of Letters Patent.

.stav-cord, as above described.

Patented Dec. so, 1919.

manner as to leave a proper length of staycord at the throat plate to start the next buttonholel e j It is, of course, important that at the beginning of the stitching on the buttonhole there shouldalways be a suflicient length of stay-cord projecting from the throat-plate so that the first stitchesof the buttonhole well be formed over the stay-cord. It is s also desirable that thereshould be no'extra length of stay-cord projecting from the "throat-plate because the presence of such exthe turningniovement ofthe turret which occurs between buttonholes, the stay-cord is subjected'to a backward pull which withdraws the cut end of the stay-cordfrom the throat-plate slightly,ithus leaving an insufficient' end projecting therefrom to start the next buttonhole, When this occurs a defective buttonhole will be produced;

f a The objectof my present invention is to provide a simple deviceforpreventing any backward movement 1 of j the stay-cord while freely permitting its forward movement, so that it willbe possible to cut the stay-cord at theend of each buttonhole and leave just the right length projecting fromthethroat-' plate to begin thefnext buttonhole without danger that this proper lengthwill" become shortened due to a backward pull of the With my invention, therefore, a proper length of stay-cord for-beginning eachbuttonhole s always insured, and t is not nec-,-

essary to provide any extra length which causes more or less waste and necessitates a tr mm ng of the cord after the buttonhole s completed. e

Inorder to give anunderstanding' of invention, I have illustrated 1n the drawings aselected embodiment thereof which 'w1ll now be described, after which thenovel fea tures will be pointed out inthe, appended 'clalms. l

Injthe drawings, Figured is; a side view of the turret of a buttonhole sew ng machine plate 2 having an aperture 9 through which opening 9 ate the work.

carrying the under thread mechanism and throat-plate and having my improvements applied thereto;

Fig. 2 is a top plan view; i

Fig. 3 is an enlarged top plan view of the throatplate showing my improved threadclamping device;

Fig. 4: is a side view of Fig. 3.

Inasmuch as my invention relates simply to the means for controlling the stay-cord, I have not deemed it necessary to illustrate herein a complete buttonhole sewing machine, but have shown in the drawings only the turret carrying the under thread mechanism to which my improvement is applied.

1 indicates generally the turret which carries the under thread mechanism and which is mounted for rotation in a suitable bearing or frame situated beneath the bed plate of the sewing machine, all as will be apparent from United States patentsnientioned above No. 1,188,942 and No. 1,255,970. The turret is provided with the throatthe upper and under needles pass and also carries the usual under needle that nianipulates the under thread and the looper which cooperates with the upper needle and the under needle in forming the edge stitches on the buttonhole. These parts are of the usual construction found in sewing machines of the type illustrated in said above-mentioned :patents and are actuated by the vertical reciprocating movement of the spindle 3 which is situated axially of the turret.

The turret 1, it will be understood, has a rotative movement during the stitching around the eye of the buttonhole and also has a-turn1ng movement during the shifting of the work from buttonholecutting to stitching position,

The throat-plate depending therefrom which is received ,in a groove 5 formed in the top of the turret,

said stem being retained in position by the clamping screw 6, this being the usual construetionin machines of this type.

The throat-plate is provided with the aperture 7 through which the stay-cord 8,

is led into the opening 9 formed in the throat-plate for the passage of the needles. said stay-cord being delivered through said The turret is also provided with a guide opening 10 through which the stay-cord extends. V i

The parts thus far described are or maybe all as usual in sewing-machines of this typ p'. I y present improvements comprise a novel thread-clamping means associated r with the "throat-plate and which operates on the thread adjacent the aperture 7 and is constructed so as to prevent backward movement of the stays-0rd 8 while freely permitting its forward movement.

The

2 has the usual stem 4 j by means of a screw 16, and said spring is so shaped that the end 15 thereof stands at a slight angle to the shoulder. This spring is made so .thatfits resiliency tends to hold the end 15 against the shoulder The arm 13 is bent laterally at its end, as

shown at 17, and is provided with a guideeye 18 through which the stay-cord passes, saidguide-eye being so positioned that the stay-cord will be guided over the shoulder 12 on its passage to the aperture? The construction of the spring 14 and its position relativeto the shoulder 12 are such as to permit the stay-cord to be freely moved forwardly from the guide-eye 18 to the aperture 7 the tensionon the cord tending to move the spring away from the shoulder 12. When the feedlng movement of ,the cord 8 ceases, theresiliency of the spring 14L causes the end 15 thereofto grip the cord against the shoulder 12, and any tendency to draw the c ord' baclnvardly will cause the endl5 of the spring lei-to lock the cord firmly against said shoulder. The spring let, therefore, permits the cords to be, freely fed, forwardly as required, but operates to prevent any backward movement ofthe cord. Thus if during the turning movement of the turret preliminary to the beginning of the stitching operation on a butt'onhole there is any tendency to draw the ,cordS backwardly, such tendency will'be resisted by the spring 14, and a proper length of cord will always be projecting through .the opening 9 inthe throatplate to insure the proper operation at thebeginning of the stitching on a buttonhole.

j I claim: 1

1. In a buttonhole sewing machine of the type'having a rotary turret carrying the under thread mechanism, the combination with a throat-plate carr ed'by said turret and provided Wvith an aperture through which the stay-cord isled to ,the work and also witlra elampingshoulderadj acent said aperture, of a resilient clamping arm cooperatmg with said shoulder to preventthe stay-cord from backward movement.

\ 2;]In a buttonhole sewing machine ofthe type having a ,rotary, turret carrying the under thread mechanism, the combination wth a throat-plateprovided with an aperlture through which the stay-cord is led, to the work and also provided with a clamping shoulder adjacent said aperture, of a stem depending from said throat-plate and by which it is secured to said turret, and a resilient clamping arm carried by said stem and cooperating with said shoulderto prevent the stay-cord from backward movement.

3. In a buttonhole sewing machine of the type having a rotary turret carrying the under thread mechanism, the combination with a throat-plate provided with an aperture through which the stay-cord is led to the work and also provided with a clamping shoulder adjacent said aperture, of a stem depending from said throat plate and by which it is secured to said turret, an arm extending laterally from said stem, and a resilient clamping member supported by said arm and cooperating with said shoulder to prevent the stay-cord from backward movement.

at. In a buttonhole sewing machine of the type having a rotary turret carrying the under thread mechanism, the combination with a throat-plate carried by said turret, said throat-plate having an opening through which the needles operate and also having both a laterally-extending aperture leading to said opening through which the stay-cord is delivered to the work and a clamping shoulder adjacent said aperture, of a resilient clamping member'cooperating with said shoulder to prevent the stay-cord from backward movement.

5. In a buttonhole sewing machine of the type havinga rotary turret carrying the under thread mechanism, the combination with the stay-cord is led to the work and also with a clamping shoulder adjacent said aperture, of a resllient clamping arm carried by said throat-plate and cooperating with said shoulder to prevent backward movement of the stay-cord.

7 In a buttonhole sewing machine of the type having a rotary turret carrying the under thread mechanism, the combination with a throat-plate provided with a stem, of means connecting the stem of said throatplate to the turret, said throat-plate having an aperture through which the staycord is led to the work, and also having a clamping shoulder adjacent said aperture, and a resilient clampingarm carried by said stem and cooperating with said shoul der to prevent backward movement of the stay cord.

In testimony whereof, I have signed my name to this specification.

JOHN KIEWICZ. 

